Pharmacology Of Antipsychotics Flashcards
What is the difference between positive and negative symptoms?
Positive: highly exaggerated ideas, perceptions, or actions that show the person can’t tell what’s real from what isn’t
Negative: absence or lack of normal mental function involving thinking, behaviour and perception
What is dementia, neurosis and psychosis?
Dementia = loss of mental powers
Neurosis = nervous disorder
Psychosis = disordered mental state
What are some examples of positive symptoms of mental illness?
Unusual experiences, hallucinations, delusions, thought disorder, feeling controlled
What are some negative symptoms of mental illness?
Loss of thought, feeling, motivation
Social withdrawal
Lack of concentration
What are some other symptoms of mental illness?
Cognitive dysfunction and depression
What causes schizophrenia?
Generic, obstetric factors
legal + illegal Drugs
Stress
What is the mechanism of action of chlorpromazine and what is its disadvantage?
D2 GPCR antagonist -> inhibition of neuronal stimulation via reduction in cAMP
Numerous side effects - sedation + movement disorders
What is the dopamine theory?
A theory suggesting increased dopamine neurotransmission is a factor in schizophrenia
All antipsychotics block post-synaptic D2 receptors in frontal cortex of brain
What are the adverse effects of antipsychotics?
- D2 Blockade - EPSEs + Hyperprolactinaemia
- Histamine blockade - Sedation + weight gain
- Anticholinergic blockade - dry mouth, urinary retention, constipation
- Alpha blockade - sedation, postural hypotension
What side effects result from a blockade of D2 receptors in the basal ganglia?
- Extrapyramidal side effects - Parkinsonism, Dystonia, Akathisia
- Hyperprolactinaemia
What drug can help treat the symptoms of tardive dyskinesia?
Clozapine
What are the symptoms of hyperprolactinaemia?
Amenorrhoea, galactorrhoea, gynaecomastia, sexual dysfunction
What are the advantages of Haloperidol over Chlorpromazine?
- no antimuscarinic / antihistamine activity
- more potent at D2
- alpha 1 adrenergic activity
What is a severe unpredictable side effect of typical antipsychotics, what are its symptoms and how is it treated?
Neuroleptic malignant syndrome (NMS)
Hyperthermia, muscle rigidity, altered mental status, elevated creatine phosphokinase
Treatment - dopamine agonists (dantrolene, benzodiazepines, bromocriptine)
